While the invention is by no means intended to be so limited, the panel assembly taught herein is particularly useful in lighting and sound applications for theatrical and concert productions, circuses, television studios, movie studios and the like. It will be appreciated that lighting equipment and sound equipment require a multitude of connections. In these applications, single conductor connectors are preferred. This is true because the cable for multiple conductor connectors is generally of large diameter, very heavy, and difficult to maneuver and transport.
When dealing with single conductor connectors, there are several important factors to consider, to prevent damage to the equipment, and for safety reasons. First of all, it is important that each individual connector be connected only to its intended receptacle. While color coding and various types of indicia are helpful in this respect, they do not preclude error. It is therefore highly desirable that means be provided making it physically impossible to mate a connector with any receptacle other than its intended receptacle. Secondly, it is frequently important, both to protect the equipment and as a safety factor, to connect and disconnect a series of connectors to and from a panel in a particular order. For example, where a ground is used, it is generally desirable that the ground makes first and breaks last.
The teachings of the present invention provide a panel assembly wherein means are provided to prevent mating of a contact with other than its intended receptacle. The system further provides means requiring the connectors to be mated with their respective receptacles in a given order, and disconnected therefrom in the reverse of that order. The panel of the present invention can serve either as an input panel or as an output panel and can be used in electrical systems requiring three, four, or five receptacles.